You talk about Heroic gear being best for world PvP, which is a given, but how does LFR gear compare to PvP gear in that respect?

In World PVP:

Conquest gear is superior to LFR gear due to the large amount of PVP power on it, and should even hold its own against flex gear fairly well, beyond that it really starts to fall behind. Honor gear is only a little bit weaker than LFR gear, but against anything beyond that it is significantly outclassed.

Prideful (S15, ilvl550) vs Warforged 4/4 gear from ordos (ilvl575). Which is better for world pvp?

My world pvp gear is currently all pvp gear except for cloak, head (with dps legendary meta), bracers, and belt. I use legendary cloak and 4/4 ordos gear (ilvl575 with additional sockets over pvp stuff). I also have chest and pants from ordos, also ilvl575, but I'm using s15 stuff instead for the set bonuses.

Prideful (S15, ilvl550) vs Warforged 4/4 gear from ordos (ilvl575). Which is better for world pvp?

My world pvp gear is currently all pvp gear except for cloak, head (with dps legendary meta), bracers, and belt. I use legendary cloak and 4/4 ordos gear (ilvl575 with additional sockets over pvp stuff). I also have chest and pants from ordos, also ilvl575, but I'm using s15 stuff instead for the set bonuses.

What class are you playing? The Ordos gear will more than likely be better just because the ilvl disparity.